package com;

import java.util.List;
import java.util.StringJoiner;

public class test {
    public static void main(String[] args) {
        Object id = "1";
        String a = (String) id;
        System.out.println(a);
        StringJoiner sj = new StringJoiner(",");
        sj.add(a);
        System.out.println(sj);
    }
}
